宁-芜矿集区及其西缘深部结构初探  

A preliminary study on deep structure of Ning-Wu ore district and its western marginal area

作　　者：杨振威[1,2] 张昆[1,2] 严加永[1,2] 陈向斌[1,2] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]国土资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《地球物理学报》2012年第12期4160-4168,共9页Chinese Journal of Geophysics

基　　金：国家科技专项"深部矿产资源立体探测技术与试验"(SinoProbe-03);国家自然科学基金项目(40930418;41104061);"十一五"科技支撑计划课题"玢岩型"铁(硫)矿深部勘查技术与找矿示范研究(2009BAB43B02);地质大调查项目"长江中下游地区地壳精细结构与控矿研究"(1212010813052)联合资助

摘　　要：为了探查宁(南京)—芜(湖)矿集区及其西缘地区上地壳结构及其与区域成矿作用的关系,在宁芜矿集区及其西缘布设两条大地电磁测深剖面(江宁区—姑山,巢湖—当涂),通过数据处理、分析和反演,获得了宁芜矿集区10km以内地壳电性结构模型.大地电磁测深及重力多尺度边缘检测结果表明:(1)宁芜矿集区自南向北表现为低—高—低的电性结构特征,南段深部存在低阻体,向上延伸至浅部,中段深部发育巨型高阻体上隆至浅部,倾向南西,推测可能是巨型花岗岩体,北段低阻体发育深度大,向上延伸至浅部时分叉并上升至地表;(2)揭示了滁河断裂和长江断裂带的存在;3线剖面东段与2线南段的低阻体位置较为一致,推测为岩浆喷发通道,在含山附近发现两条电性梯度带,3线剖面的电性结构特征可能反映了区域经历了先挤压、后拉伸的演变过程.To explore the upper crust structure and the relationship with regional mineralization in Ning-Wu ore district and its western area,two magnetotelluric sounding profiles（Jiangning district—Wuhu city,Chaohu city—Dangtu county） were finished in the Ning-Wu ore district and its western area.Crustal electric structure within 10 km is obtained by data processing analyzing and inversion.The results of magnetotelluric and gravity WORMS are summarized as follows（1） The electrical structural characteristic in Ning-Wu ore district is low-high-low from north to south.Low resistivity body is found in the south and extends upward to the shallow.Giant high resistivity body extends upward to shallow in the middle of profile 2,and it dips to the southwest.We speculated that it is a large-scale granite body.There is a deep low resistivity body in the north,extending and bifurcating at the shallow and upward to the ground.（2） Profile 3 revealed the existence of Chuhe fault and Changjiang fault.The location of low resistivity body is consistent in profile 2 and profile 3.We speculated that the low resistivity body is magma eruption channel.Two electrical gradient zones are found nearby Hanshan,and the electrical structural characteristic of profile 3 reflects that the region experienced the process of compression first then followed by stretching.

关 键 词：大地电磁测深 宁芜矿集区 电性结构 岩浆喷发通道 断裂带 

分 类 号：P631[天文地球—地质矿产勘探]